Air-compressor.



II/I. C. WHITE.

AIR COMPRESSOR. l APPLICATION FILED DEC. 3l. 1913. lymw. Patented Aug. 3,1915.

3 SHEETS-SHEET l IVI. C. WHITE. AIIICOMFRISSSH.r APPLICATION FILED Dc.3I. I9I3.

Patented Aug. 3, 1915.

3 SHEETS-SHEET 2.

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IL.; WITNESS ES IVI. C. WHITE.

AIR COMPRESSOR. /IPPLICATICfIl FILED DEC. SI. 1913.

lmGQ, PamedAug. 3, 1915.

3 SHEETS-SHEET 3.

l, chamber from which such so compressed,

MORRIS C. WHITE, OF LOS ANGELES,

CALIFORNIA, ASSIGNOR TO IVI. C. WHITE COMPANY,

AIR-COMPRESSOR.

Specification of Letters Patent.

Patented Aug. 3, i915.

Application filed December 31, 1.913. Serial No. 809,657.

To all whom it may concern Be it known that I, Monnls C. WHITE, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented new and useful Improvements in Air- Compressors, of which the following is a specification.

This invention relates to compressors, and more particularly to air compressors of the rotary type in distinction from compressors of the reciprocating type, and wherein the air or other fluid is compressed under the action of one or more rotors which force successive charges of air, initially supplied at atmospheric pressure, into a compression air or other fluid, may be withdrawn for use.

More particularly the invention relates to a two-rotor type of air compressor, the rotors of which are jointly operated, and mutually coperat'e to pass to the compression chamber the air supplied to them.

A liquid seal enters with importance into the operation of the compressor, lic|uid being fed to the rotors to effectively pocket the air picked up by the same prior to passage to the compression chamber; such portions of the seal being carried over into the compression chamber with the air compressed and successively ybuilding up a material body of such liquid within the compression l' chamber', which body in turn forms a constant source of supply for the seal of the rotors as just mentioned. This liquid body also serves as a temperature equalizer for the hot compressed air received within the compression chamber; and auxiliary cooling means are provided to extract from such liquid body the heat units imparted to it by the compressed air. The liquid seal preferably consists of a lubricating oil, andthe same is fed not only to the rotors for the purpose of more effectively' pocketing the air taken up by the same for compression, but also passes over allthe working surfaces of the rotors and the bearings thereof, being so fed and distributed under the pressure of the compressed air in the compression chamber.

I further provide means for minimizing the superficial area of the working parts between which and the compression chamber direct communication exists. In this manner I relieve the working parts of the excessive load or pressure which would otherwise exist. The compression zone of the rotors being thus reduced to minimum proportions, the friction and wear and tear upon working parts, such as the bearings of the rotors, is greatly reduced. I also provide efficient means for preventing any es cape of compressed fluid through the fiuid intake passage. It results from the provision and combination of the above generally designatedfeatures, that in practicing the invention high economy accompanies extreme efficiency, all with respect to speed of operation and power consumed.

rIlie invention has for further objects the provision of an improved compressor whic will be relatively, simple and inexpensive in construction when the other features of superiority are taken into consideration, and which will be generally superior in efficiency and adaptability 'to varying conditions and classes of use and service.

The invention consists in the novel and useful provision, formation, construction, combination and association and relative arrangement of parts, members and features, all as hereinafter described, shown in the drawings, and finally pointed out in claims.

In the drawings: Figure 1 is a vertical transverse central sectional view, taken on the line acl-:111, Fig. 2, and looking in the direction of the appended arrows; Fig. 2 is a view similar to Fig.- l taken at right angles thereto upon the line .mL-m2, Fig. 1, and looking in the direction of the appended arrows; Fig. 3 is a detail transverse sectaken upon the line aia-m3, Fig.

tional View, 1, and looking in the pended arrows; Fig. 4 is a fragmentary vertical sectional view through the walls of the rotor chamber, and illustrating the lubricant and seal supply means for the rotors; Fig. 5 is a plan view of the rotors and their shafts, the same being shown assembled together and in detached position, and upon a reduced scale; and Fig. 6 is a fragmentary vertical transverse sectional view of a portion of the rotor chamber walls, the same illustrating a modified form of construction.

Corresponding parts in all the figures are designated by the same reference characters Referring with particularity to the drawings, the improved compressor is shown as direction of the apico comprising in the main a compression chamber A, and a rotor chamber B within which are housed, in the form of construction illustrated, two rotors C andD which cooperate in the forced passage of air or other fluid from the rotor chamber to the compression chamber. T l

E designates means of communication between such chambers.

F designates an air supply chamber' through the several parts of which air passes to the rotor chamber, being taken in past a check valve f which is applied te air inlet ports 7.

G designates a compressed air outlet for the compression chamber A, the same having a nipple or connection 8 whereby the product of the compressor may be directly supplied for luse or storage.

designates cooling means provided within the compression chamber, for withdrawing the heat generated in compression,

, both from the.compressed air and the liquid seal, a material body of which is constantly retained within the compression chamber or awell a at the bottom thereof. Such seal,

' within as above stated, is preferably composed of a lubricant which is supplied to the rotors for4 the purposes of lubrication and rotor sealing as directed and controlled by liquid supply means b.

c designates a pressure shield interposed between the rotors or the rotor chamber and the compression chamber, and whereby the working surfaces of the rotors are relieved from the pressure within the compression chamber save at such portions of the rotors, constituting the working zone thereof, which are successively brought into the field of the means of communication E between the pressure chamber and the rotor chamber.

al designates auxiliary liquid supply means whereby the lubricant seal within the compression chamber may be likewise passed in small quantities to the rotor chamber, to augment the supply thereof through the means or in .substitution for the supply of such means. As the lubricant seal within the compression chamber A is always subjected to the pressure produced or maintained therein, the lubricant supplied to the rotor chamber by the means b or d, or both, is always so supplied under the pressure obtaining in the compression chamber, whereby a sure and positive feed and distribution is provided.

In the drawings l have shown one form of air compressor organized to embody the invention, and I will now describe the same, without any intent to limit the invention in its true interpretation to any of the details of such exemplary structure.

To include a casing for the rotorchamber B, and a suitable base for the entire compressor, I provide a lower body member 9 which is formed the rotor chamber for joint rotation therein, by means'of shafts 13 and 13a, journaled in the end walls of the rotor chamber, and the latter of which constitutes a drive shaft whereby suitably applied power causes the joint rotation of the intermeshing rotors. The body portion 9 or rotor chamber casing is likewise provided with curved air passages 14, exteriorly of the rotor chamber walls 1l, and included within the air supply chamber F, such pas# sages opening at their lower ends into the rotor chamber. A suitable drip-cock 15 is provided just above the base 10 of the rotor chamber, to drain the same as desired.

As clearly shown in Fig. 5, the rotors are formed or provided with intermeshing teeth 16 of the herringbone type, each of such teeth being thus V-shaped and extending from end to end of the rotor body. The air passages 14 extend to the top of the casing 9, and such top portion is provided with two concentric seats, an inner seat 16c and an outer' seat 17, within which suitable gaskets or packing rings 18 are respectively received for inner and outer annular casing walls, 19 and 20 respectively, between which is provided an annular air passage 21 communicating with the air passages 14 in the casing 9; and within the innermost, 19, of which is inclosed the compression chamber H. Within the upper portion of the casing 9 thelubricant well, or two-part well, a, is provided, such well being subdivided by a transverse bridge 22 through which passes the means of communication E between the rotor chamber and the compression chamber; said latter means including a tie bolt 23 threaded into the bridge 22 and engaging at its head 23a with and above a circular crown 24 which is provided with annular seats 25 and 26 for packing rings or gaskets 27 against which abut the upperends of the casing walls 19 and 20. The means'of communication E further include a duct or passage 25a produced through the pressure shield c at the merger portion 12 of the walls 11, and communicating thus with the rotor chamber B and with a duct or passage 26 produced by hollowing the bolt 23 lengthwise; the bolt further being provided with a plurality of perforations 2?@ leading outwardly from the passage 26 within the zone of the cooling'means H. These latter means and surrounding the bolt 23, the respectiveV ends 28a and 28b of such coil leading upwardly and outwardly, as does the outlet Gr, through the crown 24. These coil ends are connected respectively with the circulation pipes of a suitable cooling system, whereby a fluid cooling medium may be passed or` l ed to play vertically upon a guide rod 34,

to and away from the air inlet ports 7 over which extends a suitable flaring shield 35 which protects said air ports from invasion byforeign substances. K

. The seal and lubricant supply means b comprises ducts 36 produced through the merger portion 12 of the walls 11 of the pressure shield c, and extending between the lubricant .well a and the end portions of the rotor chamber B. Suitable needle valves 37 are provided at the end walls of the casing 9 controlling the flow of lubricant through the ducts. 36. -Branch ducts 38 extend divergently downwardly from each duct 36 across the respective end wall 9'*L of the rotor chamber B, so as to be swept bythe respective ends of the rotor bodies in their rotation, such branch ducts communicating with further yducts 39 produced in the walls 40 of the boxes which receive the journals or ends f of the shafts 13 of the rotors.

Three of the shaft ends are receivedin inclosed boxes 41 having bearing walls 40 and the other shaft end, namely the driving end of the shaft 13", is received in a suitable anti-friction bearing 42 to which is applied a suitable stuffing box 43.

0The auxiliary seal and lubricant supply means d comprises a feed valve 44 which taps into the lubricant Awell. a, traversing one of the' air passages 14, and having a vent 44a whereby a controlled drip or flow of lubricant may pass into the rotor chamber through such air passage 14. Anoverflow pipe 45 is arranged upright within the compression chamber H, rising from the shield c, and provided at its outwardly projecting lower end with a try cock 46 whereby the level of the seal or lubricant within the compression chamber may be maintained at the proper height toy suiiiciently surround the ssv coil 28, and provide sufficient Huid for the purposes of sealing the rotors and lubricating the same.

Baliles 47 are provided in the annular air passage 21 above the air passages 14, to prevent violent flow of fluids from the rotor chamber into the air passage 21, in the V the inter-spaces through the ducts equalizing of pressure as between the spaces,

and particularly consequent upon the cessa-l j tion of operation of the compressor, andthe consequent unchecked down-rush of iuid into the rotor chamber. Each of the herring-bone teeth of the rotor bodies is provided at its apex with a reliefaperture or vent or notch'16a, whereby the entrapped v liquid between two adjacent teeth is permitted to escape in the intermeshing of the teeth of the two rotors, after the airbrought into the working zone of the rotors has been passed to the compression` chamber,

walls 11, communlcating with .the duct 25' in the pressure shield 9. As the teeth 16 inter-mesh the lubricant-or seal liquid impounded between them is squeezed out into this slot or cut, from the apices of the interspaces between the rotor teeth, and passes through the duct 25 with th`e air forced upwardly through the means E. The release ofv the impounded fluid is particularly necessary in initiating operation, when certain ofthe interstices between the herring-bone teeth will be filled with accumulated fluid.

The mode of operation and advantages of the improved compressor constituting the invention will be readily understood from the foregoing description, taken in connection with the accompanying drawings and following statement: The rotors are constantly operated in the direction indicated by the arrows yin Fig. 1, air provided through the passages 14 being carried upwardly in the intr-spacesbetween the teeth upon the rotors and confined by the chamber walls 11. When suchl air is brought into the contracted working zone beneath the passage 25 of the means E, which zone includes portions of a limited number of the teeth 16a and the inter-spaces between the same, it is forced by the moving teeth upwardly through the means E and inio the compression chamber A, through the perforations 27a in the hollow bolt 23. The lubricant seal supplied to the rotors and to between the 4teeth 16a, 26 of the supply means b, effectively impoundsl the air in such interspaces between therotor teeth, preventing leakage or escape in any-direction,l and insuringA high eiiciency by compelling all of active because v terspace.

find final compression and storage within the chamber A. Such seal substance is released through the apex notches 16a, and

through the slot or cut 48, prior to complete inter-meshing of the successive inter-engaging teeth,-.thus the liquid sealing contents ofy such interspaces. It will be noted that the lubricant seal is admitted to the interspaces between the teeth 16a through the ducts 38 after such interspaces have taken up and confined their charges of air. The lubricant seal, under pressure of the compression chamber A acts to compress this charge of confined air in each interspace and from each end of such interspace, vproducing a compressed air bubble at the central zone of the interspace, which is ready for discharge to the com# pression chamber through the passage 25a,

followedVv by the-lubricant which is itself of its introduction under pressure, and ,is squeezed outl through the 'passage'25a afterthe air, such charge of lubricant having been cut off from the supply through the ducts 38 by the intermeshing of the teeth at the ends of the rotors, which teeth confine the respective interspaces andthe tooth which enters such in- The herringbone form of the teeth 16 prevents a jamming or locking as between the rotors, as the lubricant and air are permitted to ydischarge when the apex notches 16a come into communication with the passagea. Such jamming or locking would occurwith rotors`having straight i teeth, such as those shown in the patent to l thel end walls 9a such inter-spaces minimized. The provision 39. The

' the rotors, namely Herring, No. 1,066,815, of July 8, 1913, or the patent to Meston, N o. 683,614, of Oct. l, 1901. The bearings of the rotors are also effectively lubricated by means of the ducts 'lubricant seal emerging from the ducts 36 enters the ends of the inter-spaces between the rotor teeth, as such teeth sweep of the rotor chamber at the bottom of the tapering wall or wall merger portion l2;- and the liquid thus received by traversesI the latter toward the apex portions thereof, from which it is finally released and expressed through the notches 4or vents 16j and cut or slot 48 as above recited. AFurther lubricant or seal liquid supply to the V had through' the supply means al, permitting flow or drip through the air passage.l4.

As only theicoiitracted working zone of the impingeinent of the through suoli means E from the compression chamber, a minimum of the pressure is brought to bear upon the bearings of the rotors, and frictional losses are thus greatly of the pressure pressure applied preventing obstruction by' rotor chamber may be.

'cient :amount of the lubricant seal is l that zone which `is in communication with the means E, receives'.

.pcrtance, and lconstitutes a particular feature of the present invention.

The lubricant or seal fluid and air jetted into the compression chamber from the hollow bolt, through the perforations 27, striling the cooling means coil 28, are reduced in temperature, and the seal or lubricant 1s thus kept sufficiently cool for proper work, and the `entire compressor prevented from becoming over-heated. The maintenance of a material supply of suoli cooled seal and lubricant liquid at the bottom ofthe oompression chamber, or within the well a, assures a constantly renewed although de- 4pleted source of supply of lubricant and seal fluid for the rotors andworking parts; and the liquid constantly jetted into the compression chamber, in finely divided foam or spray, is permitted to assume its proper consistency and to become de-aerated before being again passed into the working parts of the compressor.

I have found in practice that if the level of the lubricant seal be kept beneath the lowermost of the z'perforations 27a in the hollow' bolt 23, or approximately at the level of the top of the well a, no part of such liquid seal will be carried'downwardly and over into the air chamber F upon cessation of operation of the compressor, as the remaining compressed air in the compression chamber A will follow the path of least resistance and escape through the hollow bolt into the rotor chamber B, and thence through the air chamber F and out through the inlet ports 7, minus any of such lubri- 1 cant seal or any appreciable portion thereof.

Therefore, under such conditions, the use of the check valve f is rendered unnecessary.

-Shouldthe amount tor normal level of the seal be such that any portionthereof will 4be forced through the rotor chamber B with practice to the particular capacities and ldimensions of the ducts 36, Ifind it advantageous to so form these that only a suiiiprothe vided .for introduction to but one of -rotor inter-spaces, between 'the teeth 16, at

a time. Aso such introduction is caused under the working pressurein the compression chamber, the supply is rapid and complete; and if such supply isextended to include more than one einter-space an unnecessary amount of such-` liquid is introduced to the rotors, requiring the expenditure of unnecessary power to expel it from the interspaces through the means of communication E. Excessive supply of such fluid puts a bigger load upon the bearings of the rotors, and unnecessarily opposes the rotation of the rotors. v

The entire compressor, because of particular provision and inter-relation of parts, and the mode of operation thereof, as recited, iscapable of long continued operation at a high rate of rotor-speed, without overheating or failure or depreciation of its working parts, permits of a high degree of compression, and is generally superior in efficiency and service ability because of the features of improvement pointed out.

As above indicated, I do not desire that the invention be limited or brought within narrow confines in its interpretation because of the particular `construction disclosed in the preceding description and statement and the accompanying drawings, all of which are merely exemplary. It is manifest that many variations may be made therefrom, by provision of equivalent and substitute parts and features, in adapting the invention to varying conditions of use vand service, all of which will come within a fair interpretation of the invention.

Having thus described my invention, I claim and desire to secure by Letters Patent:

1. A compressor, comprising a compression chamber adapted to contain a fluid other than that compressed, means for forcing Huid to be compressed to said compression chamber, and a further chamber communicatingV with said first named chamber and in which said iuid forcing means is contained; said compression chamber communicating with said other chamber plurally at both ends of the first-named means.

2.k A compressor, comprising a compression chamber, a rotor chamber communieating with said compression chamber, intermeshing rotors in said rotor chamber, said rotors having teeth producing interspaces there-between, and further means of communication between said compression chamber and said rotor chamber and whereby fluid other than that to be compressed is inducted successively to the interspacesv of one of said rotors at the ends of the same after fluid to be compressed has been confined in such interspaces.

3. A compressor, comprising a compres# sion chamber, a rotor chamber communicating with said compression chamber, intermeshing rotors in said rotor chamber, said rotors having teeth producing interspaces there-between, and further means of communication between said compression chamber and said rotor chamber and whereby fiuid 'other than that to be compressed is inducted successively to the interspaces of one of said rotors at the ends of the same after fluid to be compressed has been confined in such interspaces; said intermeshing teeth being angular to produce apices at which the two fluids are discharged from said rotor chamber to said compression chamber.

4. A compressor, comprising a compression chamber, a rotor chamber communicating with the compression chamber, intermeshing rotors in the rotor chamber having teeth producing interspaces, and further means of communication between said compression chamber and said rotor chamber whereby fluid other than that to be compressed is i11- ducted from the compression chamber to the rotor chamber at both ends of both of said rotors andthe interspaces thereof after fluid to be compressed has been confined. in said interspaces whereby initial compression of the fluid to be compressed is caused under the pressure of such inducted iuid.

5. A compressor, comprising a compression chamber, a rotor chamber, said compression chamber being vadapted to contain a fiuid other than that to be compressed, intermeshing rotors in said rotor chamber, and a cover for said compression chamber; there being means of communication between said chambers comprising a tie-bolt in part hollow holding said cover to said compression chamber and communicating -with both of said chambers.

In testimony whereof,I have signed my name to this specification in the presence of two subscribing witnesses.

MORRIS C. WHITE.

Witnesses:

RAYMOND Ivns BLAKESLEE, f G. ROY PENDELL. 

